Question

(akar 28 - akar 12 ) ( 2 akar 7 + 2 kar 3 ) =

Answer 1

Akar 28= 2 akar 7
akar 12= 2 akar 3.
jadi
(2 akar 7 - 2 akar 3) (2 akar 7 + 2 akar 3)
(2akar7 x 2akar7) + (2akar7 x 2akar3) - (2akar3 x 2akar7) - (2akar3 × 2akar3)
=(4x7)+4akar2 - 4akar2 - (4x3)
=28-12
=16